Just like with our search for a McDonald's in Iraq, we've been asked to help a reader locate a shocking McD's location somewhere in the globe. This time: the rumored existence of the Golden Arches within one of the caves at Carlsbad Caverns State Park.

The claim comes from the reader's coworker, who remembers there being a McDonald's down in the dark depths back in the 1970s, when he was a child. Curious to see if Ronald McDonald's magic had permeated the ground, we started digging, and this is what we foundÖ

While most of the US State Department's travel warnings seem pretty obvious--Don't vacation in Sudan? No problem!--an update yesterday concerned a surprising destination: Belize. Usually considered a safe and easy intro to Central America, it seems the country's extensive ecotourism facilities are more dangerous than we'd have guessed.

Following a fatal accident at the Cave Branch Archeological Park in September 2008, the Belize Tourism Board (BTB) is implementing new regulations, effective and legally enforced beginning October 15, 2008, to improve safety at cave tubing attractions. Those policies will include an enhanced, mandatory guest-to-guide ratio of eight-to-one for all operating cave tubing tour companies in Belize.

Additional signage will be posted in each cave tubing excursion site, informing participants of park rules and current water conditions and/or warnings. Mandatory specialty training for each cave tubing guide will continue and include education on new regulations. Helmets will also be required for each cave tubing participant starting January 1, 2009.

Diving can also be dangerous, not because of intrinsic risks, but because of ill-maintained equipment or poor decisions on the part of dive operators and boat crews. If you end up left behind at the dive site, don't say Condi Rice didn't warn you!

An urban myth was ruined during our climb down into the Mammoth Cave near Margaret River: No wooly mammoth bones were ever found there. This cave just got its name because itís really, really big.

But thereís nothing disappointing about the experience of Mammoth Cave. Although itís one of half a dozen in the area, itís the only one you can explore at your own pace without a nagging guide explaining for the hundredth time how stalactites are formed.

All those crazy cave formations you learned about in school are on view, plus an underground lake and a huge climb out the other side. And while you donít need ropes or a helmet lamp, claustrophobics probably shouldnít apply.

And with all the tourists listening to their self-guided audio tours, the cave is quiet. And eerie. Just like a cave should be.

Looks like you'll need to cancel your Ugandan spelunking trip! A Dutch tourist on a cave tour in the African nation came down with the Marburg virus and later died. Now the World Health Organization is warning people against entering caves where bats live, as they are the suspected vector for the virus.

A WHO spokesman tells the BBC:

People should not think about amending their travel plans to Uganda but should not go into caves with bats.

The fatal Marburg virus is similar to Ebola and suffice it to say it's not something you want to catch. If terrifying ailments aren't your thing, perhaps a wildlife spotting trip to neighboring Rwanda is more your speed?

Eleuthera is typically a very quiet island. There is not much to do here except lay on the beach, snorkel here and there, collect seashells and eat. Conch salad is the Bahamian specialty, but the islanders also fry anything they can get their hands on.

But should you want to some low-impact activity that's entertaining and informative, not to mention a little spooky, we say hit up Preacher's Cave.

A weekend write-up on fun on Australia's Gold Coast let us know that there is actually more stuff there than overrated fun parks (even if they do have great rollercoasters). Among other suggestions is a trip to see the glow worm caves of the national park just inland from the Gold Coast.

The tip is to take a night tour because you won't see so much glow-power during the day. An organized trip also means the tour company takes care of the restrictions on visitor numbers. You'll head out to the Natural Bridge cave, watch the glow worms and then get to eat Aussie cake for dinner. To be honest, we don't know much about these glow worms but we do know that cake is delicious.

Snakes are a big part of the traveling myth Down Under, and a caving trip through the Capricorn Caves near Rockhampton, Queensland, might be the trip that brings you face to fang with a slithery python. (Don't worry, they're usually the harmless ones.) There are bats, too, and a few other creepy-crawlies to keep the hikes and cave climbs exciting.

What we especially like are the parts of the caves covered on a Wild Caving Adventure tour. You have to squeeze through spots with names like Rebirth and Fat Man's Misery, which sound not so much fun as challenging.

Coming up soon is the Summer Solstice Light Spectacle in the caves, when light from the sun directly overhead hits just the right angle to naturally illuminate the cave. (It's sorta like that scene in Raiders of the Lost Ark where Indiana Jones holds up the Staff of Ra.) The special caving tours run from December through to early January but have a peak on December 22 when the sun beam hangs around the longest. Here's hoping the snakes stay away on solstice day.

This week Down Under, the Jenolan Caves Trust near Sydney has re-opened the Nettle Cave, and is offering a self-guided tour. They locked up this cave three-quarters of a century ago, for reasons they can't bring themselves to tell us (we're worried that it's because it wasn't interesting enough for visitors). But as of last Monday, you can use the new pathways, boardwalks and railings to see this old, old cave for yourself.

The big attractions here are the stromatolites, ancient life-forms shaped like the tail of a crayfish or lobster. Wanna know where they come from? Helpful tourist information from the good people at Jenolan tells us:

They are formed by colonies of cyanobacteria bonded with layers of calcite crystal.

All clear now? Looks like they'd make great 3D alternatives to an inkblot test, too.

If you're cruising the Midwestern states on a road trip, there's more than meets the eye when it comes to attractions. Sure, it's known for flatness. And agriculture. But there's so much more going on below the surface...literally.

In Illinois, Iowa and Ohio you can find your pick of caves to explore, if you've got a thing for stalactites (mnemonic: they're 'tied' to the ceiling) or stalagmites (you 'might' trip over them) or if you just want to explore a place that is a constant refreshing 54 degrees Fahrenheit. Find the cave closest to you at any tourist pamphlet stand.

We recommend Seneca Caverns in Bellevue, Ohio because it has the best motto, ever: "The Caviest Cave in the USA."